The eight-hour search and rescue exercise involved roughly 200 federal and state officials, miners, local law enforcement, emergency responders and other personnel. While the mock disaster focused on West Elk mine, employees from across Arch's national network of mines participated in various capacities, including mine rescuers, family and media relations personnel and performance evaluators. A total of 12 mine rescue teams participated, eight teams from Arch's mining operations, two MSHA-run teams and two teams from neighboring Oxbow and Bowie mines.

"We're sharpening skills we hope we never need to use," said Gene DiClaudio, president of Arch Western Bituminous Group, LLC. "This all-hands-on-deck, collaborative approach reinforces essential skills that will help us prepare for any situation."

MSHA was on site to participate in all components of the voluntary exercise. The scenario was scripted with various challenges and twists that unfolded as the day progressed. Participants did not know the outcome of the scenario in advance. Actors, a smoke machine and other effects were used to make the drill as realistic as possible. During the exercise, new technologies were deployed, including real-time mapping, underground tracking and MSHA's new emergency command vehicle.

"Mine rescue teams are the backbone of emergency response in the mining industry," said Joseph A. Main, assistant secretary of labor for mine safety and health. "Since there is no such thing as being overly prepared for a mine emergency, we believe very strongly in the value of these types of exercises."

U.S.-based Arch Coal is one of the world's largest and most efficient coal producers, with more than 160 million tons of coal sold in 2010. Arch Western Bituminous Group employs approximately 1,200 people in Utah and Colorado, including its West Elk mine near Somerset and its administrative office in Grand Junction.

In 2010, Arch's lost-time safety incident rate of 0.46 was the company's best yet, and five times better than the industry average of 2.52 incidents per 200,000 employee-hours. Arch Coal has a total of 20 mine rescue teams positioned across its national network of mines.